Quarterly journal of microscopical science . lying close to the pore-canal. Stone-canal normal, leadingto the slight ly-lobed hydrocoele. Amniotic invagination formed. Plight : axial sinus and pore-canal rudimentary leaving novisible lumen. Dorsal pore absent. No rnadreporic vesiclefound on this side. Hydrocoele as large as that of the leftside, but. simply vesicular in shape. Stone-canal has in itsposterior part a distinct lumen and its calibre is as thick asits left fellow ; but the canal passes into a solid cell-string asit goes dorsad towards the vestigial axial sinus. No amnioticinvaginat
Quarterly journal of microscopical science . lying close to the pore-canal. Stone-canal normal, leadingto the slight ly-lobed hydrocoele. Amniotic invagination formed. Plight : axial sinus and pore-canal rudimentary leaving novisible lumen. Dorsal pore absent. No rnadreporic vesiclefound on this side. Hydrocoele as large as that of the leftside, but. simply vesicular in shape. Stone-canal has in itsposterior part a distinct lumen and its calibre is as thick asits left fellow ; but the canal passes into a solid cell-string asit goes dorsad towards the vestigial axial sinus. No amnioticinvagination formed. (b) Left hydrocoele and its associated structure more or lessincomplete. Such is found very rarely, and hitherto any SITUS INVERSUS IN ECHINOIDS 123 definitely-recorded case belonging to this category is the kind permission of Professor Mac Bride I examinedhis preparations and found among twenty whole mounts onlya single specimen with the right echinus-rudiment larger thanthat of the left side. [Case 9.] Text-fig. Transverse sections of a fifteen-day-okl double-hydrocoele larva of Echinus miliaria, in which the water-vascular aystem of the left side has begun to degenerate. < , amniotic invagination ; axial sinus ; . dp, dorsal pore g, stomach; hy, hy, hydrocoeles; mv, madreporic vesicle; oe, oesophagus ; pr. pore-canal ; st, ??•>. Btone-canala-. [Case 10.] Echinus miliaris. Culture 9, larva was found to have double hydrocoele when fifteendays old, and then killed and examined by means of Bections(Text-fig. 3). Left: Axial sinus quite reduced, being represented by NO. 201 K 124 HIROSHI OHSHIMA a solid thickening at the dorsal end of the stone-canal, whilethe latter also has no visible lumen (sf). Pore-canal repre-sented by a solid cell-mass (pc). Hydrocoele simple andvesicular Oiy). Xo amniotic invagination. Right : anterior coelom well developed (ax), with its externalcommunication through a pore-canal (pc) and dorsal
Size: 1631px × 1531px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1850, bookpublisheroxfor, bookyear1853
